Various exhaust gas treatment devices, such as particulate filters and other devices, may be used to limit exhaust emissions of internal combustion engines. A treatment system for an exhaust gas of a diesel engine may include a diesel particulate filter (DPF) to reduce emissions of particulate matter (soot) generated during combustion.
A DPF acts as a trap of particulate filter for removing the particulate matter from the exhaust stream. The DPF may include noble metals such as platinum and/or palladium, which serve as catalysts, to further oxidize black carbon and hydrocarbons that are present in the exhaust stream.
In many cases, the DPF can be regenerated or cleaned using superheated exhaust gas to burn off the accumulated particulate matter. The DPF may be regenerated, or cleaned, after a predetermined soot level is reached. The DPF may be regenerated by modifying the combustion process of the diesel engine or injecting fuel into the exhaust stream in order to increase the temperature of the exhaust gas.